 |
|
|
|
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On 17-5-2010 22:23, Patrick Elliott wrote:
> On 5/17/2010 5:07 AM, Stephen wrote:
>> On 17/05/2010 12:51 PM, Warp wrote:
>>> For example, ask anybody, an expert or layman, why you can die from
>>> touching an electrical wall socket (which has at most 230 volts), but
>>> usually not from an electric cattle fence (which has tens of kilovolts)
>>> and you won't get a straight, rational answer. I have yet to get a
>>> proper answer from anybody (which wouldn't seem to violate the basic
>>> "U=RI" formula).
>>>
>>
>> It is all to do with current and the path it takes. Cattle fences have a
>> limited amount of current and it is dc. Domestic supplies are ac and
>> although the current is limited it is in the region of amps. It is the
>> current that kills you. More importantly id the current passed through
>> your heart the ac component disrupts the electrical signals to the heart
>> and in the heart so it starts to fibrillate that is the signals to
>> better as it is his subject.
>>
> Mind, a 9 volt battery will do the same thing, but you have to have
> direct contact to your insides, since the skin has too much resistance.
> Apparently, there is a standing rule on ships that you *do not* stab
> yourself with leads, connected to a 9 volt battery, precisely due to
> some moron trying this. Then again, I may just be propagating a rumor of
> something that happened. But, someone who was in the military told me
> about it.
>
Applying a 9 volt battery directly on the heart is the standard way to
induce fibrillation. I wasn't aware that somebody tried this on himself
without the backup of a heart-lung machine.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Stephen wrote:
> On 17/05/2010 8:21 PM, andrel wrote:
>> A defibrillator gives a short 'DC'-pulse that stimulates all cells in
>> the heart at once, and resets them. Hopefully the heart will then reboot
>> gracefully
>
> As a side note I was taught that it was important to remove any metallic
> body jewellery from around the chest area before using a defibrillator.
> Ouch!
> Another point about electrocution is that mains voltage is not always
> and one 800V dc that really woke me up. Insulating footwear is a
> lifesaver. :-D
I was told it was all metal jewelery, but that could also be caused by
the use of electric scalpels and the possibility of ground issues.
That is really not what you want to hear from a surgical nurse or
anesthesiologist, that the hospital might have grounding issues.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On Mon, 17 May 2010 17:52:32 -0400, Sabrina Kilian wrote:
> I was told it was all metal jewelery, but that could also be caused by
> the use of electric scalpels and the possibility of ground issues.
Mythbusters tested this one - their result (by no means definitive,
though) was that a burn could happen only if the defibrillator was used
incorrectly.
http://mythbustersresults.com/episode88
Jim
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Warp wrote:
> Darren New <dne### [at] san rrcom> wrote:
>> Warp wrote:
>>> clipka <ano### [at] anonymousorg> wrote:
>>>> Note that the probability that you're making contact with the cattle
>>>> wire at the very moment that a pulse has just started is /very/ low.
>>> You make it sound like touching the fence is about the same as touching
>>> a 1.5-volt battery poles. Wouldn't that kind of defeat the whole purpose?
>
>> The farmer doesn't want to kill the cow. He wants to tingle the cow enough
>> that the cow learns not to lean against the fence.
>
> Hence 1.5 volts isn't going to do it.
Yes, but a very brief high spike, which is what you were responding to,
*will* do it if the cow is pressing against the fence for several seconds.
He didn't say 1.5 volts. *You* said 1. volts. He said very short pulses.
--
Darren New, San Diego CA, USA (PST)
Ada - the programming language trying to avoid
you literally shooting yourself in the foot.
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On 05/17/10 06:13, Warp wrote:
> Invisible <voi### [at] devnull> wrote:
>> It's current that kills you, not potential difference or anything else.
>
> No, it's not the current that kills you. It's the power transfer.
>
> You yourself said it: Even if the current is tens of kilovolts, it may
> still not kill you.
Yes, but a voltage supply in the kiloamps range just may...
--
A man attempting to walk around the world DROWNED today...
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On 17/05/2010 10:52 PM, Sabrina Kilian wrote:
> I was told it was all metal jewelery, but that could also be caused by
> the use of electric scalpels and the possibility of ground issues.
>
be removed on admission. A burn from a necklace while painful and
unsightly is a talking point in at the bar. But a burn on the delicate
tissue people are piercing nowadays could be a little more painful.
> That is really not what you want to hear from a surgical nurse or
> anesthesiologist, that the hospital might have grounding issues.
--
Best Regards,
Stephen
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
On 17/05/2010 10:56 PM, Jim Henderson wrote:
> On Mon, 17 May 2010 17:52:32 -0400, Sabrina Kilian wrote:
>
>> I was told it was all metal jewelery, but that could also be caused by
>> the use of electric scalpels and the possibility of ground issues.
>
> Mythbusters tested this one - their result (by no means definitive,
> though) was that a burn could happen only if the defibrillator was used
> incorrectly.
>
It is not unknown, you know. Especially in the field.
> http://mythbustersresults.com/episode88
>
> Jim
--
Best Regards,
Stephen
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
And lo On Mon, 17 May 2010 13:46:29 +0100, Warp <war### [at] tagpovrayorg> did
spake thusly:
> Aydan <hes### [at] hendrik-sachsenet> wrote:
>> When you put the glass over the candle, the air inside the glass will
>> be warmer
>> than the environment. When the candle has used up all the oxygen, the
>> air will
>> cool down and the inside pressure sinks, sucking in the water from the
>> outside.
>
> Yeah. You wouldn't believe how convoluted explanations I have seen.
Just to act on the dumb side. If you use a graduated beaker with a candle
in it, add the water, and the second beaker, and then measure the water
height. Shouldn't the increase in temperature in the up-turned beaker
create a high-pressure that forces the water out from under it and thus an
increase in the water height as measured in the graduated beaker? So why
is the level of water forced out by the high-pressure less than the amount
'sucked' in by the low-pressure?
:-)
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > Darren New <dne### [at] sanrrcom> wrote:
> >> Warp wrote:
> >>> clipka <ano### [at] anonymousorg> wrote:
> >>>> Note that the probability that you're making contact with the cattle
> >>>> wire at the very moment that a pulse has just started is /very/ low.
> >>> You make it sound like touching the fence is about the same as touching
> >>> a 1.5-volt battery poles. Wouldn't that kind of defeat the whole purpose?
> >
> >> The farmer doesn't want to kill the cow. He wants to tingle the cow enough
> >> that the cow learns not to lean against the fence.
> >
> > Hence 1.5 volts isn't going to do it.
> Yes, but a very brief high spike, which is what you were responding to,
> *will* do it if the cow is pressing against the fence for several seconds.
> He didn't say 1.5 volts. *You* said 1. volts. He said very short pulses.
I didn't say he said 1.5 volts. I said that "you make it sound like it was
like 1.5 volts or something" (instead of a huge shock).
--
- Warp
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
| |
|
|
Phil Cook v2 <phi### [at] nospamrocainfreeservecouk> wrote:
> Just to act on the dumb side. If you use a graduated beaker with a candle
> in it, add the water, and the second beaker, and then measure the water
> height. Shouldn't the increase in temperature in the up-turned beaker
> create a high-pressure that forces the water out from under it and thus an
> increase in the water height as measured in the graduated beaker? So why
> is the level of water forced out by the high-pressure less than the amount
> 'sucked' in by the low-pressure?
I didn't understand the question.
--
- Warp
Post a reply to this message
|
|
| |
| |
|
|
|
|
| |
